An infected hip prosthesis in a dog diagnosed with a Tc-99m-ciprofloxacin (infecton) scan

This case report describes the use of the Tc-99m-labeled radiopharmaceutical ciprofloxacin (Infecton) in a case of hip prosthesis loosening in a dog. Serial planar radiographs were not conclusive, and culture of the synovial fluid was negative. Antibiotic treatment did not result in improvement of the lameness. Scintigraphy was performed with Tc-99m-Infecton, a tracer claimed to be specific for infection. Antibiotic treatment was interrupted 6 leeks prior to the examination. Planar and tomographic images at 3 h and at 24 h postinjection showed increased activity along the acetabulum and the proximal femoral bone surrounding the femoral prosthesis, indicating focal infection. Bacteriology performed after removal of the implant revealed Pseudomonas aeruginosa.